1. Field of the Invention
The present invention relates to a light-emitting semiconductor diode (LED) that uses a Group III nitride compound. More particularly, it relates to an LED having an improved emission efficiency in tho ultra violet region.
2. Description of the Background Information
A known light-emitting semiconductor diode (LED) using a Group III nitride compound comprises an n+-layer comprising GaN, an n-layer comprising Al0.08Ga0.92N, an emission layer comprising In0.08Ga0.92N, and a p-layer comprising Al0.08Ga0.92N. The known LED's emission mechanism uses inter-band recombination of electrons to obtain ultra violet color light with a peak wavelength of 380 nm or shorter.
However, the LED has a low luminous efficiency for several reasons, including a dislocation caused by a mismatch of lattice constants among the n′-layer, the n-layer, and the emission layer which invites poor crystallinity of the emission layer made of InGaN.